In the longitudinal study of children of affectively ill parents and well parents, parent-child relationships have been evaluated in early childhood. In this study, mother-child interaction and child perceptions of maternal support were assessed for two siblings, ages 8-11 years and 12-16 years. The objective of the study is to examine affective/communicative patterns, comparing affectively ill and well mother-child dyads: a) Are there particular patterns of interaction more common in dyads with mothers who have affective illnesses? b) Do these mother-child patterns of interaction differ for children at different developmental periods and of different gender? c) Do these patterns differ with children who have or do not have psychiatric disorders themselves? d) Is maternal current psychiatric status linked more closely with dysfunctional interaction patterns than is maternal lifetime diagnosis? Relational difficulties, observed in interaction and revealed through child representation, were linked to both maternal affective illness and child psychiatric status. The results illuminate interactive processes through which psychopathology may be perpetuated in families.